field-test

Context

Unit tests (add-test skill) verify handler logic with mocked context. Field testing exercises the real HTTP transport with real JSON-RPC: starts the server, calls initialize, surfaces the catalog, runs inputs, and checks what a client actually sees. It catches what unit tests miss — awkward input shapes, unhelpful errors, missing format output, drift between structuredContent and content[], edge-case surprises.

Actively call the tools. Don't read code and guess.

Transport coverage

This skill drives an HTTP server because curl + JSON-RPC is the most reliable harness for shell-based agents. The same handlers run on both transports — only the framing differs — so HTTP exercises the full functional surface. Both HTTP session modes are covered: a durable Mcp-Session-Id session, and the sessionless initialization a MCP_SESSION_MODE=stateless server performs.

Stdio coverage is a boot check only — run this before Step 1. Run bun run rebuild && bun run start:stdio < /dev/null, and confirm the startup logs look clean: the Core services constructed — N tool(s) … record lists every registered tool, resource, and prompt in its tools / resources / prompts fields — the message text shows only counts — and a definition missing from them was never passed to createApp(). No errors/warnings, no missing-config gripes. The emoji startup banner prints only to a terminal, so its absence from an agent's shell is not a finding. Redirecting stdin is what ends the run: the server treats EOF as a shutdown signal, boots fully, then exits on its own, so the log also shows the graceful-shutdown path. Do not background it and reach for pkill — a pattern like pkill -f dist/index.js matches every other stdio MCP server on the machine, including the ones the calling agent's own session is connected to. Pino logs go to stderr in stdio mode (stdout is reserved for JSON-RPC), so they print straight to the terminal when you run interactively. No need to call tools over stdio — the HTTP pass already covered handler behavior.